Dulayymi, Juma'a R. Al; Baird, Mark S.; Bolesov, Ivan G., Journal of the Chemical Society. Perkin transactions II, 2000, # 7, p. 1603 - 1618
作者:Dulayymi, Juma'a R. Al、Baird, Mark S.、Bolesov, Ivan G.、Nizovtsev, Alexey V.、Tverezovsky, Viacheslav V.
DOI:——
日期:——
Alkane elimination from ionized alkanols
作者:John L. Holmes、Peter C. Burgers、Yousuf A. Mollah
DOI:10.1002/oms.1210170305
日期:1982.3
AbstractThe energetics, metastable characteristics and daughter ion structures for the loss of small alkane molecules from ionized 2‐propanol, 2‐butanol and 3‐pentanol have been examined in detail. [2‐Propanol]+˙ ions lose CH4 to generate the keto and enol forms of [C2H4O]+˙ and the same daughter ions are produced by loss of C2H6 from [2‐butanol]+˙. Ionized 3‐pentanol does not lose CH4 but readily eliminates C2H6 to produce the enol ion [CH3CHCHOH]+˙. The last reaction was shown to proceed by a simple 1,2 elimination mechanism in the μs time‐frame; isotope effects are also discussed.
Synthesis and Reactivities of Cp*Ir Amide and Hydride Complexes Bearing C−N Chelate Ligands
A series of 16-electron Cp*Ir amide complexes with C-N chelating ligands, Cp*Ir[kappa(2)(NC)-(NHCR2-2-C6H4)] (2a: R = C6H5, 2b: R = CH3) and the chiral version, Cp*Ir[kappa(2)(N,C)-(R)-NHCH(CH3)-2-C10H6}] (2e), were obtained in good to excellent yields from reactions of 18-electron iridium amine complexes, Cp*IrCl[kappa(2)(N,C)-(NH2CR2-2-C6H4)] (1a: R = C6H5, 1b: R = CH3) and Cp*IrCl[kappa(2)(N,C)-(R)-NH2CH(CH3)-2-C10H6}] (le), with a base. The amido complexes 2 readily reacted with 2-propanol to convert into hydrido(amine) complexes 3 in almost quantitative yields. The chiral amido complex has proven to serve as an efficient catalyst for asymmetric transfer hydrogenation of acetophenone with 2-propanol, giving 1-phenylethanol with a moderate ee. The Bronsted basicity on the metal-NH moiety in the amido complexes was evaluated by deprotonation of acetic acid, dimethyl malonate, and acetone, leading to the corresponding acetato(amine) complex 4 and alkyl(amine) complexes 5 and 6, respectively, indicating that the amido-Ir complexes bearing the C-N chelate have more basic properties than those with N-sulfonylated diamine ligands.